Courage is knowing what not to fear. - Plato

The greatest and noblest conceptions have no image wrought plainly for human vision, which he who wishes to satisfy the mind of the inquirer can apply to some one of his senses and by mere exhibition satisfy the mind. We must therefore endeavor by practice to acquire the power of giving and understanding a rational definition of each one of them; for immaterial things, which are the noblest and greatest, can be exhibited by reason only, and it is for their sake that all we are saying is said. But it is always easier to practice in small matters than in greater ones.

... when someone sees a soul disturbed and unable to see something, he won't laugh mindlessly, but he'll take into consideration whether it has come from a brighter life and is dimmed through not having yet become accustomed to the dark or whether it has come from greater ignorance into greater light and is dazzled by the increased brillance.

If men learn this, it will implant forgetfulness in their souls; they will cease to exercise memory because they rely on that which is written, calling things to remembrance no longer from within themselves, but by means of external marks. What you have discovered is a recipe not for memory, but for reminder. And it is no true wisdom that you offer your disciples, but only its semblance, for by telling them of many things without teaching them you will make them seem to know much, while for the most part they know nothing, and as men filled, not with wisdom, but with the conceit of wisdom, they will be a burden to their fellows.